Analog to Digital converter

[amirmk]

Hello, I'm buulding my home studio and am about to purchase a sound card with digital I/Os only, the RME 9652. It features three ADAT optical I/Os and one S/PDIF I/O.
The DAC's avilable on the market are either medicore quality or very expensive, so I've decided to build my own 12 channel DAC, one A to D and one D to A.
Is it possible to build one myself?

Thanks.

[jcx]

saving money is not the common outcome of designing/building/debugging/verifying/interfacing sophisticated mixed signal electronics for you own use - when there is a large, competitive market full of the product you want

doesn't something like the emu 1820m fit your needs? - far better than I could build for US$400 - its highly unlikely emu designed/debugged/tested, wrote drivers, packaged, sourced parts... for this product for less than US$250K

you might be able to buy the parts in small quantity for under the US$400 the emu 1820M would cost - maybe

[amirmk]

Thank you for you answer.
I think I'll go with your idea and replace the soundcard instead of all the hard work in building a ADC.
Can you tell me please about a sound card that could be expanded to recive 18 analog inputs? no preamps are needed.
Thanks again.

[violetaudio]

many on the market,

A new really good quality one is the ESI unit, it can go to 32 channels.

[kexik]

man, don't be fool and stick to your rme... all you need is to buy some expansion cards with IO from rme (check their web), or several 8ch adat IO's, such as behringer's ada8000 (don'nt worry, it's quite pro stuff for that price and there's still room for some DIY tweaking - you can replace cheap opamps inside, or eventually AD/DA chips, they are pin compatible with AKM stuff!).
rme dsp allows you extensive routing with virtually no latency, in this price range the best solution, if you want to take 16 channels at once!

[violetaudio]

RME is good I agree, but no reason for a person not to try other products which may be better for his/her solution. the MAXIO32 has huge potential, for the price they charge it is feature rich and veryhigh quality piece, we know that in several countries they are using this with protool rigs as well. Where would we be without giving other products a look? (at least a look)

[DragonMaster]

Once you find something with I2S inputs and outputs, building an ADC or DAC should be easy. TI has a couple of different 24/96-192 ADCs on their website.

[jcx]

building something is never the problem, building something with equal usability that actually delivers better specs than even the bottom end of the commercial products available today is the hard part

actually delivering 118 dB s/n in loop back like emu 1820m requires a commitment to significant testing, refinement and respinning pcb multiple times - not a hobbyist level of effort, and it doesn't come with just buying chips with better specs

[rfbrw]

A 16ch ADAT I/O ADC/DAC is a fairly straightforward, though not inexpensive, device that is far from beyond the ken of a skilled hobbyist.

[DragonMaster]

building something with equal usability that actually delivers better specs than even the bottom end of the commercial products available today is the hard part

Well, if a kit can be found, I guess it's worth the try. There are chips with 138dB s/n that you can get from BB/TI, but could you be able to make it 138dB. You would need expensive parts like OPA627 and an optimal layout to be able to do this.